Horticulturae

41 pages, 1590 KiB

Open AccessFeature PaperEditor’s ChoiceReview

Methodologies in the Analysis of Phenolic Compounds in Roselle (Hibiscus sabdariffa L.): Composition, Biological Activity, and Beneficial Effects on Human Health

by Bety W. Hapsari, Manikharda and Widiastuti Setyaningsih

Horticulturae 2021, 7(2), 35; https://doi.org/10.3390/horticulturae7020035 - 23 Feb 2021

Cited by 31 | Viewed by 9645

Abstract

Roselle (Hibiscus sabdariffa L.), as an edible flower, has long provided an array of positive effects on human health. This benefit is a result of phenolic compounds that are naturally present mainly in the calyx. Plentiful medicinal remedies and functional foods based [...] Read more.

Roselle (Hibiscus sabdariffa L.), as an edible flower, has long provided an array of positive effects on human health. This benefit is a result of phenolic compounds that are naturally present mainly in the calyx. Plentiful medicinal remedies and functional foods based on this flower are available worldwide, as supported by the studies of phenolic compounds in recent decades. This paper aims to provide a comprehensive review of the composition, biological activity, and beneficial effects on human health of phenolic compounds in roselle. This review was performed in accordance with the Preferred Reporting Items for Systematic reviews and Meta-Analyses (PRISMA) guidelines. A structured search in the published literature for phenolics compositions in roselle was required prior to the evaluation on the validity of the reported analytical methods. Reliable identification and quantification of phenolic compounds in roselle can be achieved by employing the proper extraction and separation methods. With ample alternative analytical methods discussed here, this review provided an aid for comprehending and selecting the most appropriate method for a particular study. The applications of the analytical methods highlighted indicated that phenolic acids, flavonoids, and their derivatives have been identified and quantified in roselle with a range of biological activities and beneficial effects on human health. It was also disclosed that the composition and concentration of phenolic compounds in roselle vary due to the growth factors, cultivars, and environmental influence. Finally, apart from the research progress carried out with roselle during the last ten years, this review also proposed relevant future works. Full article

(This article belongs to the Special Issue Biodiversity, Production, Processing and Quality along the Chain of Herbal and Edible Flowers)

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13 pages, 958 KiB

Open AccessFeature PaperEditor’s ChoiceArticle

Higher Temperatures Decrease Fruit Size in Strawberry Growing in the Subtropics

by Christopher Menzel

Horticulturae 2021, 7(2), 34; https://doi.org/10.3390/horticulturae7020034 - 23 Feb 2021

Cited by 16 | Viewed by 4536

Abstract

Five strawberry (Fragaria × ananassa Duch.) cultivars were grown in Queensland, Australia to determine whether higher temperatures affect production. Transplants were planted on 29 April and data collected on growth, marketable yield, fruit weight and the incidence of small fruit less than [...] Read more.

Five strawberry (Fragaria × ananassa Duch.) cultivars were grown in Queensland, Australia to determine whether higher temperatures affect production. Transplants were planted on 29 April and data collected on growth, marketable yield, fruit weight and the incidence of small fruit less than 12 g until 28 October. Additional data were collected on fruit soluble solids content (SSC) and titratable acidity (TA) from 16 September to 28 October. Minimum temperatures were 2 °C to 4 °C higher than the long-term averages from 1965 to 1990. Changes in marketable yield followed a dose-logistic pattern (p < 0.001, R²s = 0.99). There was a strong negative relationship between fruit weight (marketable) and the average daily mean temperature in the four or seven weeks before harvest from 29 July to 28 October (p < 0.001, R²s = 0.90). There were no significant relationships between SSC and TA, and temperatures in the eight days before harvest from 16 September to 28 October (p > 0.05). The plants continued to produce a marketable crop towards the end of the season, but the fruit were small and more expensive to harvest. Higher temperatures in the future are likely to affect the economics of strawberry production in subtropical locations. Full article

(This article belongs to the Section Fruit Production Systems)

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43 pages, 1167 KiB

Open AccessFeature PaperReview

Understanding Root Rot Disease in Agricultural Crops

by Bruce A. Williamson-Benavides and Amit Dhingra

Horticulturae 2021, 7(2), 33; https://doi.org/10.3390/horticulturae7020033 - 22 Feb 2021

Cited by 50 | Viewed by 18055

Abstract

Root rot diseases remain a major global threat to the productivity of agricultural crops. They are usually caused by more than one type of pathogen and are thus often referred to as a root rot complex. Fungal and oomycete species are the predominant [...] Read more.

Root rot diseases remain a major global threat to the productivity of agricultural crops. They are usually caused by more than one type of pathogen and are thus often referred to as a root rot complex. Fungal and oomycete species are the predominant participants in the complex, while bacteria and viruses are also known to cause root rot. Incorporating genetic resistance in cultivated crops is considered the most efficient and sustainable solution to counter root rot, however, resistance is often quantitative in nature. Several genetics studies in various crops have identified the quantitative trait loci associated with resistance. With access to whole genome sequences, the identity of the genes within the reported loci is becoming available. Several of the identified genes have been implicated in pathogen responses. However, it is becoming apparent that at the molecular level, each pathogen engages a unique set of proteins to either infest the host successfully or be defeated or contained in attempting so. In this review, a comprehensive summary of the genes and the potential mechanisms underlying resistance or susceptibility against the most investigated root rots of important agricultural crops is presented. Full article

(This article belongs to the Section Genetics, Genomics, Breeding, and Biotechnology (G2B2))

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15 pages, 1588 KiB

Open AccessFeature PaperArticle

Modulating Vapor Pressure Deficit in the Plant Micro-Environment May Enhance the Bioactive Value of Lettuce

by Chiara Amitrano, Youssef Rouphael, Stefania De Pascale and Veronica De Micco

Horticulturae 2021, 7(2), 32; https://doi.org/10.3390/horticulturae7020032 - 22 Feb 2021

Cited by 18 | Viewed by 5115

Abstract

Growing demand for horticultural products of accentuated sensory, nutritional, and functional quality traits has been driven by the turn observed in affluent societies toward a healthy and sustainable lifestyle relying principally on plant-based food. Growing plants under protected cultivation facilitates more precise and [...] Read more.

Growing demand for horticultural products of accentuated sensory, nutritional, and functional quality traits has been driven by the turn observed in affluent societies toward a healthy and sustainable lifestyle relying principally on plant-based food. Growing plants under protected cultivation facilitates more precise and efficient modulation of the plant microenvironment, which is essential for improving vegetable quality. Among the environmental parameters that have been researched for optimization over the past, air relative humidity has always been in the background and it is still unclear if and how it can be modulated to improve plants’ quality. In this respect, two differentially pigmented (green and red) Salanova^® cultivars (Lactuca sativa L. var. capitata) were grown under two different Vapor Pressure Deficits (VPDs; 0.69 and 1.76 kPa) in a controlled environment chamber in order to appraise possible changes in mineral and phytochemical composition and in antioxidant capacity. Growth and morpho-physiological parameters were also analyzed to better understand lettuce development and acclimation mechanisms under these two VPD regimes. Results showed that even though Salanova plants grown at low VPD (0.69 kPa) increased their biomass, area, number of leaves and enhanced Fv/Fm ratio, plants at high VPD increased the levels of phytochemicals, especially in the red cultivar. Based on these results, we have discussed the role of high VPD facilitated by controlled environment agriculture as a mild stress aimed to enhance the quality of leafy greens. Full article

(This article belongs to the Special Issue Nutritive Value, Polyphenolic Content, and Bioactive Constitution of Green, Red and Flowering Plants)

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22 pages, 7654 KiB

Open AccessEditor’s ChoiceArticle

Evaluating the Drought Endurance of Landscaping Ground Cover Plants in a Roof Top Model

by Nath Pichakum and Aussanee Pichakum

Horticulturae 2021, 7(2), 31; https://doi.org/10.3390/horticulturae7020031 - 13 Feb 2021

Cited by 1 | Viewed by 3146

Abstract

Vegetative ground covers are commonly used in urban, tropical roadside gardens. Such landscaping ground covers usually encounter extreme water-deficits and high temperatures from vehicles and urban infrastructures. However, information about the plant species that are appropriate for low maintenance gardens is not available, [...] Read more.

Vegetative ground covers are commonly used in urban, tropical roadside gardens. Such landscaping ground covers usually encounter extreme water-deficits and high temperatures from vehicles and urban infrastructures. However, information about the plant species that are appropriate for low maintenance gardens is not available, especially in tropical areas. This study aimed to investigate potential indicators for evaluating plant tolerance to water-deficit situations. A non-irrigated rooftop model was used to test 25 commercial ground cover species in a greenhouse at Mahidol University, Nakhon Pathom Province, Thailand. Each of these 25 species was potted and subjected to one of two conditions: with or without irrigation for 7 days. Physiological responses relevant to plant endurance during water-deficits were monitored, including changes in leaf relative water content (RWC), percent stomatal opening, leaf surface temperature, leaf total chlorophyll content, leaf greenness, maximum quantum yield, and light quantum yield. Moreover, an additional indicator of landscape utility was evaluated, where each species was judged by trained panelists for their esthetic appeal. Diverse responses were observed based on the type of physiological parameter measured, plant species, and duration of drought conditions. Water withdrawal for three days was deemed an appropriate time to determine plant tolerance to water-deficit conditions, as signs of stress were clearly observed in three parameters, i.e., changes in leaf RWC, percent stomatal opening, and esthetic score. Lastly, cluster analysis revealed that seven plant species were appropriate for tropical, urban ground covers, as they had high endurance under water-deficit conditions, namely, Allium schoenoprasum,Liriope muscari, Aloe sp., Sedum x rubrotinctum, Alternanthera ficoidea, Pilea libanensis and Plectranthus scutellarioides. Full article

(This article belongs to the Section Floriculture, Nursery and Landscape, and Turf)

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11 pages, 2048 KiB

Open AccessArticle

Characteristics and Trends of Strawberry Cultivars throughout the Cultivation Season in a Greenhouse

by Min Gyu Ahn, Dong Sub Kim, Su Ran Ahn, Ha Seon Sim, Steven Kim and Sung Kyeom Kim

Horticulturae 2021, 7(2), 30; https://doi.org/10.3390/horticulturae7020030 - 9 Feb 2021

Cited by 22 | Viewed by 5168

Abstract

Each strawberry (Fragaria × ananassa) cultivar has its own growth and yield characteristics. However, the characteristics of many cultivars have not been determined at a consistent time and place, making direct comparative analysis difficult. The objective of this study was to [...] Read more.

Each strawberry (Fragaria × ananassa) cultivar has its own growth and yield characteristics. However, the characteristics of many cultivars have not been determined at a consistent time and place, making direct comparative analysis difficult. The objective of this study was to identify characteristics and trends of five Korean strawberry cultivars in the same environment during an entire season. Therefore, environmental factors such as daily average air temperature, daily average relative humidity, daily average solar radiation, daily soil temperature, daily soil water content, daily soil electrical conductivity (EC), plant growth characteristics such as the number of leaves, plant height, leaf length, leaf width, and crown diameter, and productivity characteristics such as flowering and fruiting were measured to investigate the possible correlations of the data over one season. The vegetative growth of “Seolhyang” and “Keumsil” was greater than that of “Jukhyang” and “Maehyang”. The yield of “Arihyang” was greater than that of all other cultivars. “Arihyang” also presented the greatest weight per number of fruits. Among environmental factors, higher variability in air temperature and soil water content was correlated to lower total fresh weight in the following week at different degrees for each cultivar. Among the cultivars, the time to the first flowering was delayed by about seven days when the number of leaves increased by one and was reduced by one day per 1 cm increase in plant height. The total fresh weight was enhanced up to 271 g per experimental unit, while the average number of leaves increased by one. The results indicate that the data can be used by those who need information regarding the characteristics of the strawberry cultivars through direct comparative analysis. Full article

(This article belongs to the Special Issue Smart Farming Techniques for Protected Horticulture Facilities)

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6 pages, 193 KiB

Open AccessEditorial

Refining Irrigation Strategies in Horticultural Production

by Arturo Alvino and Maria Isabel Freire Ribeiro Ferreira

Horticulturae 2021, 7(2), 29; https://doi.org/10.3390/horticulturae7020029 - 9 Feb 2021

Cited by 4 | Viewed by 3229

Abstract

Water, energy and food security are crucial for a sustainable long-term economy [...] Full article

(This article belongs to the Special Issue Refining Irrigation Strategies in Horticultural Production)

15 pages, 1173 KiB

Open AccessFeature PaperEditor’s ChoiceArticle

Effects of Fertigation Management on the Quality of Organic Legumes Grown in Protected Cultivation

by María del Carmen García-García, Rafael Font, Pedro Gómez, Juan Luis Valenzuela, Juan A. Fernández and Mercedes Del Río-Celestino

Horticulturae 2021, 7(2), 28; https://doi.org/10.3390/horticulturae7020028 - 7 Feb 2021

Cited by 5 | Viewed by 2988

Abstract

Appropriate fertigation management plays an important role in increasing crop quality and economizing water. The objective of the study was to determine the effects of two fertigation treatments, normal (T100) and 50% sustained deficit (T50), on the physico-chemical quality of legumes. The determinations [...] Read more.

Appropriate fertigation management plays an important role in increasing crop quality and economizing water. The objective of the study was to determine the effects of two fertigation treatments, normal (T100) and 50% sustained deficit (T50), on the physico-chemical quality of legumes. The determinations were performed on the edible parts of peas, French beans and mangetout. The trials were conducted in a protected cultivation certified organic farm. The response of legumes to the treatments varied between the cultivars tested. The fertigation treatments had a significant effect on the morphometric traits (width for mangetout and French bean; fresh weight for French bean; seed height for Pea cv. Lincoln). The total soluble solids and citric acid content have been shown to be increased by low soil water availability (T50) for mangetout. Fertigation treatments did not significantly affect the antioxidant compounds (total phenolic and ascorbic acid), minerals and protein fraction contents of legumes studied. Regarding legume health benefits, the most prominent cultivars were BC-033620 pea and French bean because of their high total phenolic (65 mg gallic acid equivalent 100 g⁻¹ fresh weight) and ascorbic acid content (55 mg ascorbic acid 100 g⁻¹ fresh weight), respectively. The results expand our knowledge concerning the nutraceutical quality and appropriate cultivation methods of legumes in order to make the system more sustainable and to encourage their consumption. Full article

(This article belongs to the Special Issue Horticultural Crop Response to Different Environmental and Nutritional Stress)

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8 pages, 925 KiB

Open AccessArticle

Bokashi, Boiled Manure and Penergetic Applications Increased Agronomic Production Variables and May Enhance Powdery Mildew Severity of Organic Tomato Plants

by Fernando Teruhiko Hata, Mauricio Ursi Ventura, Gustavo Adolfo de Freitas Fregonezi and Romário Fortunato de Lima

Horticulturae 2021, 7(2), 27; https://doi.org/10.3390/horticulturae7020027 - 6 Feb 2021

Cited by 12 | Viewed by 3858

Abstract

Research on organic fertilizers are of crucial importance for sustainable production systems with high efficiency of natural resource use. The objective of this study was to evaluate organic sources of fertilization (boiled manure (BM), effective microorganism (EM) Bokashi, and Penergetic) for their effects [...] Read more.

Research on organic fertilizers are of crucial importance for sustainable production systems with high efficiency of natural resource use. The objective of this study was to evaluate organic sources of fertilization (boiled manure (BM), effective microorganism (EM) Bokashi, and Penergetic) for their effects on agronomic variables (fruit size and yield, total soluble solids) and on foliar powdery mildew severity of tomato (Solanum lycopersicum L.). The crops were grown during two cropping cycles in protected cultivation. The treatments were: Control (water only); 50 g per plant of EM Bokashi compost in two applications; Penergetic at 1.5 g L⁻¹ applied to the substrate before planting or sprayed on the plants 14 days after transplanting; and BM at 2.5%, 5.0%, 7.5%, and 10% concentrations (vol/vol) in water, via fertigation. Fruit production and quality were assessed. The effects of treatments on powdery mildew (Leveillula taurica Lév. G. Arnaud) were analyzed by using a diagrammatic scale. Bokashi, 10% BM, and Penergetic increased fruit production of the first three fruit trusses. Bokashi treatment increased tomato fruit diameter. The effects on fruit length and total soluble solids varied with each crop cycle. Powdery mildew severity increased with 10% BM, compared to the control. Both 10% BM and Penergetic presented similar fruit production to Bokashi and are good candidates as substitutes for Bokashi as organic fertilizers/amendments while maintaining tomato yield. Full article

(This article belongs to the Section Vegetable Production Systems)

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7 pages, 1822 KiB

Open AccessCommunication

Fruit Morphology Measurements of Jujube Cultivar ‘Lingwu Changzao’ (Ziziphus jujuba Mill. cv. Lingwuchangzao) during Fruit Development

by Yaping Ma, Dapeng Zhang, Zhuangji Wang, Lihua Song and Bing Cao

Horticulturae 2021, 7(2), 26; https://doi.org/10.3390/horticulturae7020026 - 6 Feb 2021

Cited by 10 | Viewed by 3498

Abstract

‘Lingwu Changzao’ (Ziziphus jujuba Mill. cv. Lingwuchangzao), a cultivar of Ziziphus in the Rhamnaceae family, is a traditional jujube cultivar in Ningxia, China. For ‘Lingwu Changzao’, morphological traits are prominent in characterizing fruit yield, quality, and consumer acceptance. However, morphological measurements for [...] Read more.

‘Lingwu Changzao’ (Ziziphus jujuba Mill. cv. Lingwuchangzao), a cultivar of Ziziphus in the Rhamnaceae family, is a traditional jujube cultivar in Ningxia, China. For ‘Lingwu Changzao’, morphological traits are prominent in characterizing fruit yield, quality, and consumer acceptance. However, morphological measurements for ‘Lingwu Changzao’ cultivation are limited. Therefore, the objective of this study is to measure the growing patterns of selected morphological traits during ‘Lingwu Changzao’ fruit development. Eight morphological traits, including four fruit traits (fruit length, diameter, weight, and flesh (mesocarp) thickness), three stone traits (stone length, diameter, and weight), and fruit firmness (also known as fruit hardness), were measured over a 3-mo (months) period, covering a completed fruit development period. Results indicate that the growing patterns of fruit traits coincide with double ‘S’ growth curves, which mainly present the growth of ‘Lingwu Changzao’ fruit. Increases of stone traits terminated in the early fruit growth period, while fruit traits continuously increased till the end of the 3-mo period. That implies a high fruit-stone ratio, i.e., a desirable quality attribute for ‘Lingwu Changzao’ as fresh-eating fruits. The results presented in this study can serve as one part of the standard dataset for jujube fruit cultivation in China, and it can also support decisions in plant breeding and field managements for ‘Lingwu Changzao’. Full article

(This article belongs to the Section Fruit Production Systems)

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13 pages, 2273 KiB

Open AccessFeature PaperEditor’s ChoiceArticle

Genomic Resource Development for Hydrangea (Hydrangea macrophylla (Thunb.) Ser.)—A Transcriptome Assembly and a High-Density Genetic Linkage Map

by Xingbo Wu, Amanda M. Hulse-Kemp, Phillip A. Wadl, Zach Smith, Keithanne Mockaitis, Margaret E. Staton, Timothy A. Rinehart and Lisa W. Alexander

Horticulturae 2021, 7(2), 25; https://doi.org/10.3390/horticulturae7020025 - 5 Feb 2021

Cited by 9 | Viewed by 4561

Abstract

Hydrangea (Hydrangea macrophylla) is an important ornamental crop that has been cultivated for more than 300 years. Despite the economic importance, genetic studies for hydrangea have been limited by the lack of genetic resources. Genetic linkage maps and subsequent trait mapping [...] Read more.

Hydrangea (Hydrangea macrophylla) is an important ornamental crop that has been cultivated for more than 300 years. Despite the economic importance, genetic studies for hydrangea have been limited by the lack of genetic resources. Genetic linkage maps and subsequent trait mapping are essential tools to identify and make markers available for marker-assisted breeding. A transcriptomic study was performed on two important cultivars, Veitchii and Endless Summer, to discover simple sequence repeat (SSR) markers and an F₁ population based on the cross ‘Veitchii’ × ‘Endless Summer’ was established for genetic linkage map construction. Genotyping by sequencing (GBS) was performed on the mapping population along with SSR genotyping. From an analysis of 42,682 putative transcripts, 8780 SSRs were identified and 1535 were validated in the mapping parents. A total of 267 polymorphic SSRs were selected for linkage map construction. The GBS yielded 3923 high quality single nucleotide polymorphisms (SNPs) in the mapping population, resulting in a total of 4190 markers that were used to generate maps for each parent and a consensus map. The consensus linkage map contained 1767 positioned markers (146 SSRs and 1621 SNPs), spanned 1383.4 centiMorgans (cM), and was comprised of 18 linkage groups, with an average mapping interval of 0.8 cM. The transcriptome information and large-scale marker development in this study greatly expanded the genetic resources that are available for hydrangea. The high-density genetic linkage maps presented here will serve as an important foundation for quantitative trait loci mapping, map-based gene cloning, and marker-assisted selection of H. macrophylla. Full article

(This article belongs to the Special Issue Breeding, Genetics and Genomics of Ornamental Plants)

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14 pages, 2969 KiB

Open AccessFeature PaperEditor’s ChoiceArticle

Effect of Bacillus spp. and Brevibacillus sp. on the Photosynthesis and Redox Status of Solanum lycopersicum

by Marino Costa-Santos, Nuno Mariz-Ponte, Maria Celeste Dias, Luísa Moura, Guilhermina Marques and Conceição Santos

Horticulturae 2021, 7(2), 24; https://doi.org/10.3390/horticulturae7020024 - 3 Feb 2021

Cited by 16 | Viewed by 4357

Abstract

Plant-growth-promoting bacteria (PGPB) are gaining attention as a sustainable alternative to current agrochemicals. This study evaluated the impact of three Bacillus spp. (5PB1, 1PB1, FV46) and one Brevibacillus sp. (C9F) on the important crop tomato (Solanum lycopersicum) using the model cv. [...] Read more.

Plant-growth-promoting bacteria (PGPB) are gaining attention as a sustainable alternative to current agrochemicals. This study evaluated the impact of three Bacillus spp. (5PB1, 1PB1, FV46) and one Brevibacillus sp. (C9F) on the important crop tomato (Solanum lycopersicum) using the model cv. ‘MicroTom’. The effects of these isolates were assessed on (a) seedlings’ growth and vigor, and (b) adult potted plants. In potted plants, several photosynthetic parameters (chlorophylls (a and b), carotenoids and anthocyanins contents, transpiration rate, stomatal conductance, net CO₂ photosynthetic rate, and intercellular CO₂ concentration, and on chlorophyll fluorescence yields of light- and dark-adapted leaves)), as well as soluble sugars and starch contents, were quantified. Additionally, the effects on redox status were evaluated. While the growth of seedlings was, overall, not influenced by the strains, some effects were observed on adult plants. The Bacillus safensis FV46 stimulated the content of pigments, compared to C9F. Bacillus zhangzhouensis 5PB1 increased starch levels and was positively correlated with some parameters of the photophosphorylation and the gas exchange phases. Interestingly, Bacillus megaterium 1PB1 decreased superoxide (O₂⁻) content, and B. safensis FV46 promoted non-enzymatic antioxidant defenses, increasing total phenol content levels. These results, conducted on a model cultivar, support the theory that these isolates differently act on tomato plant physiology, and that their activity depends on the age of the plant, and may differently influence photosynthesis. It would now be interesting to analyze the influence of these bacteria using commercial cultivars. Full article

(This article belongs to the Collection Microbe-Assisted Production of Horticultural Crops)

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14 pages, 1527 KiB

Open AccessFeature PaperEditor’s ChoiceArticle

Nutraceutical Content and Daily Value Contribution of Sweet Potato Accessions for the European Market

by Aline C. Galvao, Carlo Nicoletto, Giampaolo Zanin, Pablo F. Vargas and Paolo Sambo

Horticulturae 2021, 7(2), 23; https://doi.org/10.3390/horticulturae7020023 - 30 Jan 2021

Cited by 7 | Viewed by 3855

Abstract

Sweet potatoes (SPs) are considered by the FAO as a primary crop for “traditional agriculture” in the tropics, but in Europe, its consumption is not widespread. However, consumer demand has grown exponentially over the past five years. This study has evaluated the quality [...] Read more.

Sweet potatoes (SPs) are considered by the FAO as a primary crop for “traditional agriculture” in the tropics, but in Europe, its consumption is not widespread. However, consumer demand has grown exponentially over the past five years. This study has evaluated the quality and nutrient contents of storage roots of 29 SPs accessions to characterize their role in improving the human diet. Roots were analyzed for nutraceuticals, sugars, and minerals. Results underlined a considerable variability of nutrient content related to color among SPs accessions. The deep-orange-fleshed SPs showed a higher content of β-carotene compared to the light orange- and cream-fleshed ones; 100 g of edible product of HON86 can supply 32.3% of the daily value contribution of vitamin A, followed by the pale orange-fleshed BRA32 and BRA54. The total phenolic content of the purple ecotypes was about two to five times higher than the other genotypes. The calcium content was generally low, whereas, in many accessions, magnesium and phosphorus content reached 20%, or higher of the contribution to the daily value. Such a high variability suggests different use of the different accessions according to their strengths, but might also be used for breeding to improve quality traits of the commercial varieties. Full article

(This article belongs to the Special Issue Nutritional and Antioxidant Value of Horticulturae Products)

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12 pages, 1482 KiB

Open AccessArticle

Latitudinal Characteristic Nodule Composition of Soybean-Nodulating Bradyrhizobia: Temperature-Dependent Proliferation in Soil or Infection?

by Md Hafizur Rahman Hafiz, Ahsanul Salehin, Fumihiko Adachi, Masayuki Omichi, Yuichi Saeki, Akihiro Yamamoto, Shohei Hayashi and Kazuhito Itoh

Horticulturae 2021, 7(2), 22; https://doi.org/10.3390/horticulturae7020022 - 29 Jan 2021

Cited by 3 | Viewed by 2704

Abstract

A species-specific latitudinal distribution of soybean rhizobia has been reported; Bradyrhizobium japonicum and B. elkanii dominate in nodules in northern and southern areas, respectively. The aim of this study was to elucidate whether temperature-dependent proliferation in soil or infection is more reliable for [...] Read more.

A species-specific latitudinal distribution of soybean rhizobia has been reported; Bradyrhizobium japonicum and B. elkanii dominate in nodules in northern and southern areas, respectively. The aim of this study was to elucidate whether temperature-dependent proliferation in soil or infection is more reliable for determining the latitudinal characteristic distribution of soybean-nodulating rhizobia under local climate conditions. Three study locations, Fukagawa (temperate continental climate), Matsue and Miyazaki (humid sub-tropical climate), were selected in Japan. Each soil sample was transported to the other study locations, and soybean cv. Orihime (non-Rj) was pot-cultivated using three soils at three study locations for two successive years. Species composition of Bradyrhizobium in the nodules was analyzed based on the partial 16S rRNA and 16S–23S rRNA ITS gene sequences. Two Bradyrhizobium japonicum (Bj11 and BjS10J) clusters and one B. elkanii (BeL7) cluster were phylogenetically sub-grouped into two (Bj11-1-2) and four clusters (BjS10J-1-4) based on the ITS sequence. In the Fukagawa soil, Bj11-1 dominated (80–87%) in all study locations. In the Matsue soil, the composition was similar in the Matsue and Miyazaki locations, in which BeL7 dominated (70–73%), while in the Fukagawa location, BeL7 decreased to 53% and Bj11-1 and BjS10J-3 increased. In the Miyazaki soil, BeL7 dominated at 77%, and BeL7 decreased to 13% and 33% in the Fukagawa and Matsue locations, respectively, while BjS10J-2 and BjS10J-4 increased. It was supposed that the B. japonicum strain preferably proliferated in the Fukagawa location, leading to its nodule dominancy, while in the Miyazaki location, temperature-dependent infection would lead to the nodule dominancy of B. elkanii, and both factors would be involved in the Matsue location. Full article

(This article belongs to the Special Issue Horticultural Crop Response to Different Environmental and Nutritional Stress)

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14 pages, 2312 KiB

Open AccessFeature PaperArticle

Alleviation of Heat Stress in Tomato by Exogenous Application of Sulfur

by Muhammad Moaaz Ali, Muhammad Waleed Shafique, Shaista Gull, Waleed Afzal Naveed, Talha Javed, Ahmed Fathy Yousef and Rosario Paolo Mauro

Horticulturae 2021, 7(2), 21; https://doi.org/10.3390/horticulturae7020021 - 29 Jan 2021

Cited by 28 | Viewed by 4667

Abstract

Temperature is a key factor influencing plant growth and productivity, however sudden increases in temperature can cause severe consequences in terms of crop performance. We evaluated the influence of elementary sulfur application on the physiology and growth of two tomato genotypes (“Ahmar” and [...] Read more.

Temperature is a key factor influencing plant growth and productivity, however sudden increases in temperature can cause severe consequences in terms of crop performance. We evaluated the influence of elementary sulfur application on the physiology and growth of two tomato genotypes (“Ahmar” and “Roma”) grown in two growth chambers (at 25 and 45 °C). Plants were sprayed with 2, 4, 6, and 8 ppm sulfur 45 days after sowing (untreated plants were kept as control). Plants of the “Roma” cultivar receiving 6 ppm sulfur exhibited maximal shoot and root biomass values followed by those receiving 4 ppm under both temperature conditions. Maximal CO₂ index, photosynthetic rate, transpiration rate, and greenness index values (188.1 µmol mol⁻¹, 36.3 µmol CO₂ m⁻² s⁻¹, 1.8 µmol H₂O m⁻² s⁻¹, and 95 SPAD, respectively) were observed in plants of “Roma” cultivar grown at 25 °C, indicating positive influences of sulfur on tomato physiology. Similarly, sulfur maximized proline, nitrogen, phosphorus, and potassium contents in leaves of both genotypes at both temperatures. The differences between control and sulfur-treated plants grown under heat stress indicate a possible role of sulfur in mitigating heat stress. Overall, our results suggest that 6 ppm of sulfur is the best dose to alleviate tomato heat stress and enhance the morphological, physiological, and biochemical attributes of tomato plants. Full article

(This article belongs to the Special Issue Molecular and Physiological Responses of Horticultural Crops to Abiotic Stresses: Effect and Improvement)

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13 pages, 1562 KiB

Open AccessEditor’s ChoiceArticle

Reassessing the Role of Potassium in Tomato Grown with Water Shortages

by Anna De Luca, Mireia Corell, Mathilde Chivet, M. Angeles Parrado, José M. Pardo and Eduardo O. Leidi

Horticulturae 2021, 7(2), 20; https://doi.org/10.3390/horticulturae7020020 - 29 Jan 2021

Cited by 12 | Viewed by 3072

Abstract

Potassium (K) is closely related to plant water uptake and use and affects key processes in assimilation and growth. The aim of this work was to find out to what extent K supply and enhanced compartmentation might improve water use and productivity when [...] Read more.

Potassium (K) is closely related to plant water uptake and use and affects key processes in assimilation and growth. The aim of this work was to find out to what extent K supply and enhanced compartmentation might improve water use and productivity when tomato plants suffered from periods of water stress. Yield, water traits, gas exchange, photosynthetic rate and biomass partition were determined. When plants suffered dehydration, increasing K supply was associated with reduction in stomatal conductance and increased water contents, but failed to protect photosynthetic rate. Potassium supplements increased shoot growth, fruit setting and yield under water stress. However, increasing the K supply could not counteract the great yield reduction under drought. A transgenic tomato line with enhanced K uptake into vacuoles and able to reach higher plant K contents, still showed poor yield performance under water stress and had lower K use efficiency than the control plants. With unlimited water supply (hydroponics), plants grown in low-K showed greater root hydraulic conductivity than at higher K availability and stomatal conductance was not associated with leaf K concentration. In conclusion, increasing K supply and tissue content improved some physiological features related to drought tolerance but did not overcome yield restrictions imposed by water stress. Full article

(This article belongs to the Special Issue Managing the Product Quality of Vegetable Crops under Abiotic Stress)

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9 pages, 1205 KiB

Open AccessFeature PaperCommunication

Evaluation of Carrageenan, Xanthan Gum and Depolymerized Chitosan Based Coatings for Pineapple Lily Plant Production

by Piotr Salachna and Anna Pietrak

Horticulturae 2021, 7(2), 19; https://doi.org/10.3390/horticulturae7020019 - 29 Jan 2021

Cited by 10 | Viewed by 3875

Abstract

Some natural polysaccharides and their derivatives are used in horticulture to stimulate plant growth. This study investigated the effects of coating bulbs with carrageenan-depolymerized chitosan (C-DCh) or xanthan-depolymerized chitosan (X-DCh) on growth, flowering, and bulb yield as well as physiological and biochemical attributes [...] Read more.

Some natural polysaccharides and their derivatives are used in horticulture to stimulate plant growth. This study investigated the effects of coating bulbs with carrageenan-depolymerized chitosan (C-DCh) or xanthan-depolymerized chitosan (X-DCh) on growth, flowering, and bulb yield as well as physiological and biochemical attributes of pineapple lily (Eucomis autumnalis). The results showed that treatment with C-DCh or X-DCh significantly increased all growth parameters, bulb yield, greenness index, stomatal conductance, total N, total K, and total sugar content of bulbs and accelerated anthesis as compared with untreated bulbs. The positive impact of coatings on plant growth and physiological attributes depended on the type of biopolymer complexes. The X-DCh treatment exhibited the greatest plant height, fresh weight, daughter bulb number, greenness index, stomatal conductance, total N, K, and sugar content. However, this treatment induced a significant decrease in L-ascorbic acid, total polyphenol content and antioxidant activity. Overall, the results of this study indicated high suitability of C-DCh and X-DCh as bulb coatings for pineapple lily plant production. Full article

(This article belongs to the Special Issue Trends in Ornamental Plant Production)

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9 pages, 702 KiB

Open AccessFeature PaperCommunication

Aqu@teach—The First Aquaponics Curriculum to Be Developed Specifically for University Students

by Sarah Milliken, Andrej Ovca, Nadine Antenen, Morris Villarroel, Tjaša Griessler Bulc, Benz Kotzen and Ranka Junge

Horticulturae 2021, 7(2), 18; https://doi.org/10.3390/horticulturae7020018 - 27 Jan 2021

Cited by 3 | Viewed by 4273

Abstract

Aquaponic food production requires a broad spectrum of knowledge in order to understand and manage the processes involved, and for commercial aquaponics to develop its full potential, it will require an appropriately trained workforce. Devised in collaboration as an Erasmus+ Strategic Partnership for [...] Read more.

Aquaponic food production requires a broad spectrum of knowledge in order to understand and manage the processes involved, and for commercial aquaponics to develop its full potential, it will require an appropriately trained workforce. Devised in collaboration as an Erasmus+ Strategic Partnership for Higher Education, Aqu@teach covers the basics of aquaponics with a focus on transferable and entrepreneurial skills. The aquaponics curriculum can either be taught using blended learning—combining digital media and the internet with classroom formats that require the physical co-presence of the teacher and students—or as an e-learning course. The supplementary entrepreneurial skills module was devised on the basis of two surveys: of aquaponics companies around the world, in order to get a broad overview of the skills that are important in the early years of a business; and of European higher education institutions that teach subjects where aquaponics could be incorporated as an optional module. The entrepreneurial skills curriculum introduces the main processes involved in developing a business idea into a start-up company. All of the Aqu@teach resources—the e-learning modules, textbooks, module guides for students, curriculum guides for teachers, best practice guide for teaching aquaponics, and toolbox of innovative didactic practices—are open access. Full article

(This article belongs to the Special Issue Aquaponics: Circular Sustainability for Food Security)

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15 pages, 996 KiB

Open AccessEditor’s ChoiceArticle

Effects of Drought on Yield and Nutraceutical Properties of Beans (Phaseolus spp.) Traditionally Cultivated in Veneto, Italy

by Pietro Sica, Aline Galvao, Francesco Scariolo, Carmelo Maucieri, Carlo Nicoletto, Cristiane Pilon, Paolo Sambo, Gianni Barcaccia, Maurizio Borin, Miguel Cabrera and Dorcas Franklin

Horticulturae 2021, 7(2), 17; https://doi.org/10.3390/horticulturae7020017 - 26 Jan 2021

Cited by 7 | Viewed by 3824

Abstract

Beans are often grown in regions with climates that are susceptible to drought during the cultivation period. Consequently, it is important to identify bean accessions tolerant to drought conditions and assess the effect of drought on seeds’ nutraceutical properties. This study evaluated the [...] Read more.

Beans are often grown in regions with climates that are susceptible to drought during the cultivation period. Consequently, it is important to identify bean accessions tolerant to drought conditions and assess the effect of drought on seeds’ nutraceutical properties. This study evaluated the effect of drought during different development stages (NES = never stressed; ALS = always stressed; SBF = stressed before flowering; SAF = stressed after flowering) on the yield and nutraceutical properties of six local bean varieties: Fasolo del Diavolo, Gialet, Posenati, Secle, D’oro, and Maron. Analysis of variance indicated that Gialet was not significantly affected by drought treatments, and Posenati under SBF and NES treatments had greater yields than under ALS and SAF treatments, whereas Secle under SBF produced 80% more seeds than under NES. Total phenols, antioxidant capacity, and calcium content were significantly different among the local varieties. Yield was significantly and positively correlated with seed calcium content and significantly and negatively correlated with protein, total phenols, and antioxidant capacity. The interaction between local varieties and treatment significantly affected seeds’ Zn content. Gialet and Maron seeds’ Zn contents were about 60 mg kg⁻¹, almost double the average of commercial varieties. In summary, this study paves the way to the identification of potential bean varieties resistant to drought. Further molecular studies will help support these findings. Full article

(This article belongs to the Special Issue Managing the Product Quality of Vegetable Crops under Abiotic Stress)

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16 pages, 1269 KiB

Open AccessArticle

Roles of Si and SiNPs in Improving Thermotolerance of Wheat Photosynthetic Machinery via Upregulation of PsbH, PsbB and PsbD Genes Encoding PSII Core Proteins

by Heba Hassan, Aishah Alatawi, Awatif Abdulmajeed, Manal Emam and Hemmat Khattab

Horticulturae 2021, 7(2), 16; https://doi.org/10.3390/horticulturae7020016 - 26 Jan 2021

Cited by 33 | Viewed by 3394

Abstract

Photosystem II is extremely susceptible to environmental alterations, particularly high temperatures. The maintenance of an efficient photosynthetic system under stress conditions is one of the main issues for plants to attain their required energy. Nowadays, searching for stress alleviators is the main goal [...] Read more.

Photosystem II is extremely susceptible to environmental alterations, particularly high temperatures. The maintenance of an efficient photosynthetic system under stress conditions is one of the main issues for plants to attain their required energy. Nowadays, searching for stress alleviators is the main goal for maintaining photosynthetic system productivity and, thereby, crop yield under global climate change. Potassium silicate (K₂SiO₃, 1.5 mM) and silicon dioxide nanoparticles (SiO₂NPs, 1.66 mM) were used to mitigate the negative impacts of heat stress (45 °C, 5 h) on wheat (Triticum aestivum L.) cv. (Shandawelly) seedlings. The results showed that K₂SiO₃ and SiO₂NPs diminished leaf rolling symptoms and electrolyte leakage (EL) of heat-stressed wheat leaves. Furthermore, the maximum quantum yield of photosystem II (Fv/Fm) and the performance index (PI_abs), as well as the photosynthetic pigments and organic solutes including soluble sugars, sucrose, and proline accumulation, were increased in K₂SiO₃ and SiO₂NPs stressed leaves. At the molecular level, RT-PCR analysis showed that K₂SiO₃ and SiO₂NPs treatments stimulated the overexpression of PsbH, PsbB, and PsbD genes. Notably, this investigation indicated that K₂SiO₃ was more effective in improving wheat thermotolerance compared to SiO₂NPs. The application of K₂SiO₃ and SiO₂NPs may be one of the proposed approaches to improve crop growth and productivity to tolerate climatic change. Full article

(This article belongs to the Special Issue Molecular and Physiological Responses of Horticultural Crops to Abiotic Stresses: Effect and Improvement)

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19 pages, 861 KiB

Open AccessEditor’s ChoiceArticle

Chemical Composition, Antioxidant, and α-Glucosidase-Inhibiting Activity of Aqueous and Hydroethanolic Extracts of Traditional Antidiabetics from Croatian Ethnomedicine

by Kristina Bljajić, Andrea Brajković, Ana Čačić, Lovorka Vujić, Jasna Jablan, Isabel Saraiva de Carvalho and Marijana Zovko Končić

Horticulturae 2021, 7(2), 15; https://doi.org/10.3390/horticulturae7020015 - 26 Jan 2021

Cited by 9 | Viewed by 3189

Abstract

Type 2 diabetes (T2D) is a chronic disease with a growing prevalence worldwide. In addition to the conventional therapy, many T2D patients use phytotherapeutic preparations. In the present study, chemical composition, antioxidant, and α-glucosidase inhibiting activity of traditional antidiabetics from Croatian ethnomedicine ( [...] Read more.

Type 2 diabetes (T2D) is a chronic disease with a growing prevalence worldwide. In addition to the conventional therapy, many T2D patients use phytotherapeutic preparations. In the present study, chemical composition, antioxidant, and α-glucosidase inhibiting activity of traditional antidiabetics from Croatian ethnomedicine (Achillea millefolium, Artemisia absinthium, Centaurium erythraea, Morusalba, Phaseolus vulgaris, Sambucus nigra, and Salvia officinalis) were assessed. The efficacy of water and 80% ethanol as extraction solvents for bioactive constituents was compared. HPLC analysis revealed that the prepared extracts were rich in phenols, especially rutin, ferulic, and chlorogenic acid. Antiradical (against DPPH and ABTS radicals), reducing (towards Mo⁶⁺ and Fe³⁺ ions), and enzyme inhibiting properties were in linear correlation with the content of phenolic constituents. Ethanolic extracts, richer in phenolic substances, showed dominant efficacy in those assays. Aqueous extracts, on the other hand, were better Fe²⁺ ion chelators and more active in the β-carotene linoleic acid assay. Extracts from S. officinalis and A. millefolium were particularly active antioxidants and α-glucosidase inhibitors. A. absinthium, another potent α-glucosidase inhibitor, contained chromium, a mineral that promotes insulin action. The investigated plants contained significant amounts of minerals useful in management of T2D, with negligible amounts of heavy metals deeming them safe for human use. Full article

(This article belongs to the Special Issue Nutritive Value, Polyphenolic Content, and Bioactive Constitution of Green, Red and Flowering Plants)

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16 pages, 1693 KiB

Open AccessEditor’s ChoiceArticle

Fertilization and Pre-Sowing Seed Soaking Affect Yield and Mineral Nutrients of Ten Microgreen Species

by Tongyin Li, Geoffrey T. Lalk and Guihong Bi

Horticulturae 2021, 7(2), 14; https://doi.org/10.3390/horticulturae7020014 - 25 Jan 2021

Cited by 17 | Viewed by 4821

Abstract

Microgreens, vegetable or herb seedlings consumed at a young growth stage, are considered to be a functional food with high concentrations of mineral nutrients and healthy beneficial bioactive compounds. The production of microgreens has been increasing in recent years. Vegetable growers are interested [...] Read more.

Microgreens, vegetable or herb seedlings consumed at a young growth stage, are considered to be a functional food with high concentrations of mineral nutrients and healthy beneficial bioactive compounds. The production of microgreens has been increasing in recent years. Vegetable growers are interested in growing microgreens as a new specialty crop due to their high market value, popularity, and short production cycles. However, there is a lack of research-based crop-specific recommendations for cultural practices including fertilization, pre-sowing seed treatments, and their effects on nutritional facts of microgreens. Ten microgreen species were evaluated for their shoot growth and mineral nutrient concentrations as affected by one-time post-emergence fertilization and pre-sowing seed soaking in two repeated experiments, from November 2018 to January 2019, in a greenhouse. The microgreen species varied in fresh and dry shoot weights, shoot height, visual rating, as well as macro- and micro-nutrient concentrations. Fertilization with a general-purpose soluble fertilizer (20-20-20 with micronutrients) at a rate of 100 mg·L⁻¹ nitrogen (N) increased fresh shoot weight, and macro- and micro-nutrient concentrations in one or both experiments, with the exception of decreasing concentrations of calcium (Ca), magnesium (Mg), and manganese (Mn). Seed soaking consistently decreased fresh or dry shoot weight and nutrient concentrations when there was a significant effect. Full article

(This article belongs to the Section Protected Culture)

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12 pages, 830 KiB

Open AccessFeature PaperArticle

Composting Spent Mushroom Substrate from Agaricus bisporus and Pleurotus ostreatus Production as a Growing Media Component for Baby Leaf Lettuce Cultivation under Pythium irregulare Biotic Stress

by Daniel Hernández, Margarita Ros, Francisco Carmona, José Antonio Saez-Tovar and Jose Antonio Pascual

Horticulturae 2021, 7(2), 13; https://doi.org/10.3390/horticulturae7020013 - 25 Jan 2021

Cited by 15 | Viewed by 4799

Abstract

Composts of spent mushrooms substrates can be an alternative for the partial replacement of peat as growing media in horticulture. Three mature composts from Agaricus bisporus (Ag), Pleurotus ostreatus (Pl), and 70% Ag:30% Pl (AgPl) production were used as partial components of peat [...] Read more.

Composts of spent mushrooms substrates can be an alternative for the partial replacement of peat as growing media in horticulture. Three mature composts from Agaricus bisporus (Ag), Pleurotus ostreatus (Pl), and 70% Ag:30% Pl (AgPl) production were used as partial components of peat growing media, used at a 1:4 compost:peat ratio for growing red baby leaf lettuce. They showed higher yields, between 3 and 7 times more than that for peat itself, even under the pressure of the plant pathogen Pythium irregulare. AgPl showed the higher suppressiveness (50%) against Pythium irregulare than Ag- (38%) or Pl- (15%) supplemented media. The combination of these raw materials and a suitable composting process is important for obtaining mature compost for use as a partial component of peat-based growing media. Full article

(This article belongs to the Special Issue Optimising Soilless Culture Systems and Alternative Growing Media to Current Used Materials)

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11 pages, 11207 KiB

Open AccessFeature PaperEditor’s ChoiceArticle

Reduced Iris Yellow Spot Symptoms through Selection within Onion Breeding Lines

by Neel Kamal, Seyed Shahabeddin Nourbakhsh and Christopher S. Cramer

Horticulturae 2021, 7(2), 12; https://doi.org/10.3390/horticulturae7020012 - 22 Jan 2021

Cited by 7 | Viewed by 2986

Abstract

Iris yellow spot (IYS) disease in onion (Allium cepa L.) is caused by onion thrips (Thrips tabaci L.) vectored Iris yellow spot virus (IYSV). The absence of cultivars that are resistant/tolerant to thrips and/or IYS is a challenge for onion bulb [...] Read more.

Iris yellow spot (IYS) disease in onion (Allium cepa L.) is caused by onion thrips (Thrips tabaci L.) vectored Iris yellow spot virus (IYSV). The absence of cultivars that are resistant/tolerant to thrips and/or IYS is a challenge for onion bulb and seed production worldwide. To measure selection progress for reduced/delayed IYS symptom expression in onion breeding lines after two selection cycles, selections were performed in 2011 on previously evaluated lines that exhibited a reduced symptom expression after one selection cycle. Selected plants from each line were massed in a cage and the resulted progenies were evaluated in 2013 and 2014 along with their original populations and a susceptible check—’Rumba’. In some comparisons, the selection progress for delayed/reduced IYS symptom expression was observed for some breeding lines. Plants of most selected breeding lines exhibited less disease expression than plants of ‘Rumba’. For some selections, a low disease severity was observed even with a relatively high number of thrips per plant. These results suggest that further improvement might be achievable with additional cycles of selection. Full article

(This article belongs to the Special Issue Advances in Allium Breeding and Genetics)

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12 pages, 288 KiB

Open AccessFeature PaperEditor’s ChoiceArticle

Tree Planting Density and Canopy Position Affect ‘Cerasuola’ and ‘Koroneiki’ Olive Oil Quality

by Filipa Grilo, Sahar Sedaghat, Vita Di Stefano, Raffaele Sacchi, Tiziano Caruso and Riccardo Lo Bianco

Horticulturae 2021, 7(2), 11; https://doi.org/10.3390/horticulturae7020011 - 20 Jan 2021

Cited by 12 | Viewed by 3023

Abstract

To maximize orchard production and tree crop efficiency, optimization of both maximum orchard light interception and radiation distribution within the tree canopy are important strategies. To study the influence of planting density and fruit position within the canopy on oil quality from ‘Cerasuola’ [...] Read more.

To maximize orchard production and tree crop efficiency, optimization of both maximum orchard light interception and radiation distribution within the tree canopy are important strategies. To study the influence of planting density and fruit position within the canopy on oil quality from ‘Cerasuola’ and ‘Koroneiki’ olive (Olea europaea L.), fruits were harvested from the upper and lower canopy layers of trees in hedgerow planting systems at two densities: High at 1000 trees ha⁻¹ (HD) and Medium at 500 trees ha⁻¹ (MD). Tree crop efficiency and fruit weight, water and fat content were measured together with olive oil standard quality parameters, phenolic and volatile composition. Fruits in the upper layers of the canopy always showed a higher maturity index, 6% more fat content, and 4% less water content than lower layers. Upper layers of HD trees showed the highest phenol content, whereas lower layers of MD trees showed the lowest phenol content (36% less than the upper layers of HD). HD trees showed the largest differences in fruit maturation, water and fat content between upper and lower canopy positions, increasing quality and oil yield variability at harvest. ‘Koroneiki’ showed more stable oils with a 28% higher MUFA/PUFA ratio and 12% higher phenol content than ‘Cerasuola’ oils. This study provides further evidence of the fact that cultivar, planting density, and canopy architecture may be strong determinants of olive oil yield and composition in hedgerow planting systems. Full article

(This article belongs to the Special Issue Feature Papers in Horticulturae Ⅱ)

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Horticulturae, Volume 7, Issue 2 (February 2021) – 25 articles

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